Parse Objective C中注销时出现PFUser错误

Question

尝试调用PFUser logoutInBackground时，我收到以下错误消息：

Error Domain=NSCocoaErrorDomain Code=4 "The operation couldn’t be completed. (Cocoa error 4.)" UserInfo=0x7af4bc00 {NSUnderlyingError=0x7cd50eb0 "The operation couldn’t be completed. No such file or directory", NSFilePath=/Users//Library/Developer/CoreSimulator/Devices/SDFDSDF-BC68-4SDF-sfdf-2GKJSKKSS/data/Containers/Data/Application/EA3BF90C-SDFJ-4153-AB1B-SDKFJNSDKJFN/Library/Private Documents/Parse/currentUser, NSUserStringVariant=(
Remove
)}

但如果我打印出PFUser currentuser，它看起来不错！

<PFUser: 0x7cccb80, objectId: iFaGeM2vT, localId: (null)> {
didFinishCreatingAccount = NO;
"first_name" = F;
"full_Name" = "F F";
"last_name" = F;
peopleIFollow =     (
);
pictureFile = "<PFFile: 0x7c95b1d0>";
resetCode = 3274;
username = "+1245********";
}

问题仍存在于设备上......